The little leaguer who crossed home plate and ran straight into a lawsuit and it turns out the guy suing him, well, it's his own coach. Abc's aditi roy is in our l.A. Bureau with what kind wind up being $500,000 worth of trouble. Reporter: Really interesting story. Alan beck says he likes his former player but that he's suing him because he wants a teenager and his family to take responsibility for what he's calling physical and emotional injuries. This teenage little league player scene in these photos is so ten of a $500,000 lawsuit for what his coach said he did while celebrating a teammate's walk-off hit. He threw the helmet like a spike. Like spiking a football. He's the strongest kid on our team, threw a helmet and clipped my achilles and tore it. Alan beck says it happened at the 13-year-old was rounding base after the game's winning hit and the team began celebrating. In court documents beck says the blow from the helmet caused him serious physical, psychological and emotional injuries. As a coach against the young man that he's supposed to be training, not just in sport, but in maturity and in life. Reporter: But beck says after failed attempts to work it out with the family, he has no choice but to sue the league, the parents and his former player. Just from the point of accountability for their son's action. He's a great kid. I love the kid, you know, it really hurts me of me doing this. Reporter: But the boy's parents say there is nothing to apologize for. He was simply joining the team's celebration. Be something like this get it out of the way so I can celebrate with my friends. Reporter: Joe and reagan paris believe the suit is frivolous and prepared to defend what they believe is a senseless curveball. You would think that something this severe and ambulance would have been called or people would have rushed to him. Beck's attorney told abc news his client is recovering from foot surgery he had yesterday receipted to the incident. Abc news reached out to the president of lakeside little league. He told us they have to comment.

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